PROJECT SUMMARY Every year, more than one million U.S. youth sport participants ages 6 to 18 are diagnosed with a concussion. After acute post-concussive symptoms have resolved, clinicians often struggle with how to discuss returning to sport with families. The decision to cease sport is very individualized and cannot be reduced to a single numeric cut-off. Influential factors in this decision include clinical variability (e.g., injury severity, recovery trajectory, type of functional impairment post-injury, the interval between prior injuries, the age at which injuries occurred, and premorbid health conditions), different family tolerance for the uncertain risk of harm associated with sustaining an additional concussion relative to what they see as the benefits of returning to sport, the risks and benefits of substitute activities, and psychosocial readiness for sport retirement. Further complicating this conversation is the lack of definitive evidence about about the potential long-term risks of contact sport and the incremental increase in risk with subsequent concussions among youth. Addressing these challenges, we seek to develop and evaluate a decision aid that helps adolescents and their parents/guardians with their clinician make an informed and value-driven decision about sport participation post-concussion. We will focus on helping shared decision making in two situations: (1) the clinician believes there is equipoise in the decision about whether to return to or cease participation in contact/collision sport, and (2) the clinician believes contact/collision sport cessation would be medically beneficial but sport disqualification is not mandatory based on current consensus guidelines. This will be accomplished with a (1) a web-based module to be completed separately by parents and adolescents pre-visit, sharing risk information and supporting values clarification related to sport participation, and (2) implementation support for clinicians to facilitate within -visit discussion, prioritization and decision-making. To develop an optimally useful decision aid, we will engage a diverse group of families and clinicians in the development process and will focus on meeting the needs of families with low health literacy. Thus, the following aims will be addressed: (1) Develop a decision aid to support shared decision-making about sport participation post-concussion using a process of user-engaged content specification and design; (2) Conduct usability testing of the decision aid in a clinical setting; (3) Conduct a pilot test of the efficacy of this decision aid in a diverse sample of families presenting to Seattle Children?s Hospital for post-concussion care. The primary outcome of the pilot clinical trial will be decisional regret. Secondarily, the impact of the tool on sport participation, physical activity and psychosocial outcomes three months post- decision will be explored. Achieving the proposed aims will result in a decision aid that is acceptable to the target populations and that has preliminary evidence of its efficacy facilitating higher quality decision making post-concussion. This will provide the foundation for a subsequent R01 application to evaluate the effectiveness of the tool in a multicenter cluster randomized controlled trial. 1